WoNS management actions must be readily adaptable to respond to the impacts of climate change. These impacts include changes in distribution and abundance of invasive plants and increased impacts of invasive plants on native ecosystems and primary production.

Climate change is listed as a key threatening process under the Environment Protection and Biodiversity Conservation Act 1999. Commonwealth, State and Territory Governments are undertaking adaptation research and developing action plans to reduce the impacts of climate change. The WoNS program supports these overarching plans and will work to incorporate climate change adaptation strategies into invasive plant management programs.

Key areas for action include:

• Identify priority areas for research and monitoring of the response of invasive plants to climate change.
• Monitor, record and analyse changes in distribution, abundance and impact of invasive plants to ensure management practices are adapted to minimize future impacts on biodiversity and primary production.
• Develop adaptation methodology and initiatives that reduce the impacts of invasive plants on biodiversity in future climates and incorporate these into management actions in conjunction with NRM regional bodies and other stakeholders.
• Research and understand the interactions between climate change, weeds, biodiversity and primary production, including negative and positive impacts: Improve knowledge of those impacts to develop specific impact reduction actions. This includes planning for situations where invasive plants may provide ecosystem functions (eg. connectivity, harbour) that may no longer be provided by native species under altered climates.
• Raise community awareness and share knowledge of the increased impacts of invasive plants on biodiversity and primary production under climate change: Provide opportunities for public participation in impact reduction actions.

Limited empirical data exist on the impact of climate change on invasive plants, or weeds. Weeds are likely to be the most successful at adapting to a warmer climate, as they are aggressive primary colonizers. Many WONS have not yet expanded to the full extent in their current predicted range, and this may occur more rapidly in a warmer climate. In addition, current ecosystems may become less resilient to invasion by weeds as climate changes: This may also assist weeds to spread further and become more dominant within their current range. Under warmer climates, WONS eco-climatic ranges are likely to change, thus allowing expansion to new environmental niches, where control options may not be available.

More critically, WONS are well-adapted to respond to landscape disturbance caused by the increased frequency and intensity of extreme weather events that will accompany a warmer climate. Events such as cyclones, flooding, drought and fires will become more common and weeds will be the first to gain a stronghold after these events. Genetic plasticity in weeds is poorly understood and this may be compounded as weeds respond to altered environmental cues brought on by climate change (eg. increased humidity may affect seed dormancy).

Climate change may affect invasive plants through:

• increased disturbance due to fire, floods and other extreme climatic events
• potential range shifts (e.g. movement towards cooler latitudes or higher elevations)
• higher temperatures and reductions in frost events
• changes in rainfall timing, frequency and levels (incl. humidity and evapotranspiration)
• reduced stream and river flows (exposing well-watered riparian areas)
• changes in coastal and estuarine habitat due to rising sea levels
• increased carbon dioxide fertilization (and resultant increases in weed growth)
• changes in pathogen pressures, including serious impacts on biological control programs
• changes to flowering and fruiting times
• changes to species interactions (e.g. between plants and pollinators, weed vectors, etc).

SITE MAP